------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 1 PID: 9001 at lib/refcount.c:25 refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 1 PID: 9001 Comm: syz.0.1025 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:refcount_warn_saturate+0xff/0x1a0 lib/refcount.c:25
Code: 09 01 48 c7 c7 40 6b 59 8a e8 dd 27 bb 05 0f 0b eb e0 e8 04 42 9c fd c6 05 ae 8f 79 09 01 48 c7 c7 80 6a 59 8a e8 c1 27 bb 05 <0f> 0b eb c4 e8 e8 41 9c fd c6 05 93 8f 79 09 01 48 c7 c7 e0 6a 59
vkms_vblank_simulate: vblank timer overrun
RSP: 0018:ffffc90000dd06a8 EFLAGS: 00010246
RAX: 6698ed0737da4f00 RBX: 0000000000000002 RCX: ffff888025e9d940
RDX: 0000000000000100 RSI: 0000000000000101 RDI: 0000000000000000
RBP: ffffc90000dd0808 R08: dffffc0000000000 R09: fffff520001ba039
R10: fffff520001ba039 R11: 1ffff920001ba038 R12: ffff888079129a80
R13: dffffc0000000000 R14: 0000000000000002 R15: 0000000000000000
FS: 00007f0a313f76c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3001fffc CR3: 000000006673b000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__refcount_add include/linux/refcount.h:-1 [inline]
__refcount_inc include/linux/refcount.h:250 [inline]
refcount_inc include/linux/refcount.h:267 [inline]
get_net include/net/net_namespace.h:252 [inline]
tipc_aead_encrypt net/tipc/crypto.c:832 [inline]
tipc_crypto_xmit+0x1949/0x2560 net/tipc/crypto.c:1772
tipc_crypto_clone_msg+0x91/0x160 net/tipc/crypto.c:1667
tipc_crypto_xmit+0x1ac5/0x2560 net/tipc/crypto.c:1728
tipc_bearer_xmit_skb+0x228/0x3c0 net/tipc/bearer.c:574
tipc_disc_timeout+0x568/0x6b0 net/tipc/discover.c:338
call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
expire_timers kernel/time/timer.c:1496 [inline]
__run_timers+0x525/0x7c0 kernel/time/timer.c:1767
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
handle_softirqs+0x328/0x820 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 9a b1 f7 48 89 df e8 56 6f b2 f7 e8 a1 13 d3 f7 fb bf 01 00 00 00 86 93 a6 f7 65 8b 05 27 a3 57 76 85 c0 74 02 5b c3 e8 d4 ad 55
RSP: 0018:ffffc9000344f7f0 EFLAGS: 00000286
RAX: 6698ed0737da4f00 RBX: ffff888076663518 RCX: 6698ed0737da4f00
RDX: dffffc0000000000 RSI: ffffffff8a0b11c0 RDI: 0000000000000001
RBP: dffffc0000000000 R08: dffffc0000000000 R09: ffffed100eccc6a4
R10: ffffed100eccc6a4 R11: 1ffff1100eccc6a3 R12: 00fff00000080017
R13: 0000000000000000 R14: ffff888076663510 R15: ffff888076663518
spin_unlock_irq include/linux/spinlock.h:413 [inline]
delete_from_page_cache+0x129/0x190 mm/filemap.c:267
truncate_inode_page+0x8d/0xb0 mm/truncate.c:219
shmem_undo_range+0x49b/0x1840 mm/shmem.c:960
shmem_truncate_range mm/shmem.c:1063 [inline]
shmem_evict_inode+0x20d/0xa00 mm/shmem.c:1145
evict+0x485/0x870 fs/inode.c:647
__dentry_kill+0x431/0x650 fs/dcache.c:586
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xd8/0x1a0 fs/dcache.c:893
__fput+0x5ee/0x930 fs/file_table.c:319
task_work_run+0x125/0x1a0 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0a3358e58a
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24
RSP: 002b:00007f0a313f6e00 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 00007f0a3358e58a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000002 R08: 0000000000000000 R09: 000000000000441b
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f0a313f6ef0 R14: 00007f0a313f6eb0 R15: 00007f0a28fd7000
----------------
Code disassembly (best guess):
0: f6 ff idiv %bh
2: 0f 1f 00 nopl (%rax)
5: 53 push %rbx
6: 48 89 fb mov %rdi,%rbx
9: 48 83 c7 18 add $0x18,%rdi
d: 48 8b 74 24 08 mov 0x8(%rsp),%rsi
12: e8 8e 9a b1 f7 call 0xf7b19aa5
17: 48 89 df mov %rbx,%rdi
1a: e8 56 6f b2 f7 call 0xf7b26f75
1f: e8 a1 13 d3 f7 call 0xf7d313c5
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 86 93 a6 f7 call 0xf7a693b5 <-- trapping instruction
2f: 65 8b 05 27 a3 57 76 mov %gs:0x7657a327(%rip),%eax # 0x7657a35d
36: 85 c0 test %eax,%eax
38: 74 02 je 0x3c
3a: 5b pop %rbx
3b: c3 ret
3c: e8 .byte 0xe8
3d: d4 (bad)
3e: ad lods %ds:(%rsi),%eax
3f: 55 push %rbp